It is known to make container closures and closure sealants using polymers with erucamide as a slip agent. However, erucamides are ethylenically-unsaturated amides that react with ozone that is used for sterilization, thereby creating aldehyde off-tastes that adversely affect beverage products such as carbonated water and soft drinks. However, the use of saturated amides, such as behenamide, while avoiding the off-taste problem, tend to be less effective as slip aids because it is believed that they migrate more slowly to the surface of the matrix polymer and thereby are less efficacious in providing a low-friction surface.
As noted in World Patent WO 0236672A1 of Alphagary Corporation, it was noted that conventional closure sealants for beverage or food containers have utilized lubricants such as erucamide and oleamide, each of which is conjugated. Because these lubricants are conjugated, they are susceptible to photochemical breakdown and oxidative breakdown. In other words, oxidative breakdown of erucamide by ozone sterilization can create flavor-detracting contaminants such as ketones in addition to aldehydes. Ozone sterilization is frequently performed to sterilize bottled water products, such as mineral water and spring water. The United States Food and Drug Administration requires ozone sterilization for sterilizing bottled water products manufactured and sold in the United States. Thus, there is a need for a closure sealant lubricant that is resistant to oxidative breakdown from ozone sterilization. Additionally, there is a need for a closure sealant lubricant that is resistant to photochemical and thermal breakdown. Exposure to ultra-violet light can also photochemically degrade erucamide and form flavor-detracting chemicals, and this adverse effect can be testing using any number of industry standard tests. Degradation of erucamide can also occur as a consequence of elevated temperatures during shipping or storage in hot climates.
Thus, a novel erucamide-free composition is needed for making container closures and closure sealants.